1. Field of the Invention
The present invention relates to a camera having auto-focus and auto-exposure functions.
2. Related Background Art
An operator can perform focusing and exposure operations at any time in a manually operated conventional camera.
In most of the recent auto-focus, auto-exposure cameras, focusing and exposure operations are automatically initiated upon depression of a shutter release button according to a first scheme. The first scheme allows even a beginner to perform easy auto-focusing and auto-exposure. However, highly technical photography cannot be performed wherein an object subjected to focusing is different from an object subjected to exposure control.
In another auto-focus, auto-exposure camera according to a second scheme, unlike the first scheme wherein auto-focus and auto-exposure operations are simultaneously started upon depression of a shutter release button, an auto-focus lock button and an auto-exposure lock button are provided to perform focusing and exposure operations at different times. According to the second scheme, after an object subjected to focusing is focused, a photometric operation is performed for an object subjected to exposure control while the auto-focus lock button is kept depressed, thus resulting in poor operability and inconvenience.
According to a third scheme, start buttons for auto-exposure and auto-focus operations are arranged, and the start of operation and the holding of the operation can be independently performed. According to the third scheme, the auto-focus start button is depressed to auto-focus an object, and then the auto-focus start button is released to maintain an auto-focused state. In this state, the camera is panned to an object subjected to exposure control. The auto-exposure start button is then depressed to perform a photometric operation. In this manner, auto-focus and auto-exposure operations can be independently performed. A camera employing this scheme can be conveniently used by a skilled user. However, operations are still complicated, and the camera of this type is not suitable for a beginner.
Thus, the conventional schemes have both advantages and disadvantages.
The conventional camera of the first scheme cannot allow highly technical photography in which an object subjected to auto-focus is different from an object subjected to exposure control. The conventional camera of the second scheme requires complicated operations in which an object subjected to auto-focus is focused and then the camera is panned to an object subjected to exposure control so as to perform the photometric operation while the auto-focus lock button is kept depressed, thereby degrading operability and resulting in inconvenience. The conventional camera of the third scheme can be conveniently used by a skilled user since the auto-focus and auto-exposure operations can be independently performed but is not suitable for a beginner.